Graduating from college and officially entering adulthood is exciting... but many recent grads are surprised by how much harder it is to make friends outside of school than it was in school. And it's true -- kids make friends way more easily than adults. For a zillion reasons: some you can help, some you can't.

I've spent a lot of time thinking about the best possible way to make more friends -- when you travel, as a child, as an adult. And this is probably THE NUMBER ONE WAY to make new friends as an adult:

***

Become a regular!

Somewhere. Anywhere. Because there are three criteria to starting a new friendship:

A) Proximity. (You can't make friends with someone who lives far away whom you never see.)B) An environment that allows you to be real, honest and vulnerable. (More on that later.)C) Regular, unplanned interactions.

Back in the good ol' days, peoples' social circles were a lot bigger than they are now. People were more involved in church and community groups. People attended meetings, instead of sending group emails. People assembled places. People knew their neighbors and borrowed tools and cups of sugar from them.

Moreover, entertainment took place outside the home. People went out to see plays and movies. People went to malls and baseball games and video arcades. They didn't binge watch Netflix all weekend and stay in to play World of Warcraftor whatever. They went to libraries to get books. They organized ice cream sociables.

Ice Cream Sociables and Evening Processions...

But today, entertainment takes place inside the home. Membership in church and community groups is down. Our "social groups" consist mainly of work friends, friends from college (who steadily get new jobs and begin moving away), and friends of friends.

Friendship (and love) is a numbers game. If you interact with fewer people regularly, you'll make fewer friends.

Now, for many adults (myself included), it's reasonably easy to meet people. All you have to do is smile and make eye contact. (Read more about specific behaviors that will improve your charisma.) Often, you even like the people you meet. But not necessarily enough to do things you wouldn't be doing anyway with them.

For example, when I first meet someone new, and I want to see them again, I invite them to play basketball, climb, or go to karaoke with me. (I mean, come on! I'm busy, and I barely know them!)

But... say I met myself, and I wanted to be friends. Real friends. We both like each other enough to be friends... but we don't know each other well enough to make plans outside of what we'd be doing anyway. BAM. We're never going to be friends. UNLESS...

We become regulars.

Seriously. I used to go to the gym just, like, whenever. Pickup games happen pretty continuously from about 4pm on, so I could show up whenever and hop into a game. But I would complain that pickup is so hit or miss. Some days, there are nine amazing players on the court. Other days, everyone sucks and no one passes to you.

But then I realized... The people I like playing with tend to play on the same days at the same times. They know each other. They like each other. And they play together, once or twice a week!

So I started going on the same days, at the same time, whenever possible. Not only has the quality and consistency of the game improved... but I've built better friendships with the people I play with. And I even like them enough, at this point, that I hang out with them outside of the gym.

And, who knows? Maybe someday, we'll join a league together. Or enter a 3x3 tournament. Or be godparents to each other's children.

Not a basketball player? This advice still applies to you. When you go to lift weights, swim, do zumba, or whatever, try to go to the same gym at the same time each week. Become a regular. And you might make some gym friends, who eventually become your real friends.

If you have a favorite bar, become a regular there. Go at the same-ish time on the same day of each week. I recommend Tuesday. I love Tuesdays.

If you like working from a coffee shop... same thing. Heck -- if you ride the same train at the same time each day... maybe it's time toget a little mindful. Put your phone down -- it's only making you depressed and boring, anyway. Except, of course, if you just got a text from one of your favorite high school teachers. Then you'll be all:

But yeah. Otherwise, put away your phone. Then smile, and make eye contact. Make friendly conversation with the people around you. And pay attention -- you might be riding the same train together every day! You could totally be train friends! And then real friends! And then godparents!

You can also join a church, volunteer organization, meet-up or anything else. Just go regularly, and you're already 2/3 of the way towards a new friendship. Now, you just need to practice the whole self-disclosure/vulnerability thing, and you'll be a master of adult friendships!